merge after 3.4.3 release

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@21705 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
4687: global name 'warn' is not defined

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@21707 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
4687: missing content migration...

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@21710 4ae1f11a-8b86-4847-b8af-ab372f36d1fd